/** @file

  Copyright (c) 2017-2018, Arm Limited. All rights reserved.

  This program and the accompanying materials
  are licensed and made available under the terms and conditions of the BSD License
  which accompanies this distribution.  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.php

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

  System Control and Management Interface V1.0
    http://infocenter.arm.com/help/topic/com.arm.doc.den0056a/
    DEN0056A_System_Control_and_Management_Interface.pdf
**/

#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Protocol/ArmScmiBaseProtocol.h>

#include "ArmScmiBaseProtocolPrivate.h"
#include "ScmiPrivate.h"

/** Return version of the Base protocol supported by SCP firmware.

  @param[in]  This     A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] Version  Version of the supported SCMI Base protocol.

  @retval EFI_SUCCESS       The version of the protocol is returned.
  @retval EFI_DEVICE_ERROR  SCP returns an SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
STATIC
EFI_STATUS
BaseGetVersion (
  IN  SCMI_BASE_PROTOCOL  *This,
  OUT UINT32              *Version
  )
{
  return ScmiGetProtocolVersion (SCMI_PROTOCOL_ID_BASE, Version);
}

/** Return total number of SCMI protocols supported by the SCP firmware.

  @param[in]  This           A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] TotalProtocols Total number of SCMI protocols supported.

  @retval EFI_SUCCESS       Total number of protocols supported are returned.
  @retval EFI_DEVICE_ERROR  SCP returns a SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
STATIC
EFI_STATUS
BaseGetTotalProtocols (
  IN  SCMI_BASE_PROTOCOL  *This,
  OUT UINT32              *TotalProtocols
  )
{
  EFI_STATUS  Status;
  UINT32      *ReturnValues;

  Status = ScmiGetProtocolAttributes (SCMI_PROTOCOL_ID_BASE, &ReturnValues);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  *TotalProtocols = SCMI_TOTAL_PROTOCOLS (ReturnValues[0]);

  return EFI_SUCCESS;
}

/** Common function which returns vendor details.

  @param[in] MessageId       SCMI_MESSAGE_ID_BASE_DISCOVER_VENDOR
                             OR
                             SCMI_MESSAGE_ID_BASE_DISCOVER_SUB_VENDOR

  @param[out] VendorIdentifier ASCII name of the vendor/subvendor.

  @retval EFI_SUCCESS       VendorIdentifier is returned.
  @retval EFI_DEVICE_ERROR  SCP returns an SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
STATIC
EFI_STATUS
BaseDiscoverVendorDetails (
  IN  SCMI_MESSAGE_ID_BASE  MessageId,
  OUT UINT8                 VendorIdentifier[SCMI_MAX_STR_LEN]
  )
{
  EFI_STATUS    Status;
  UINT32        *ReturnValues;
  SCMI_COMMAND  Cmd;
  UINT32        PayloadLength;

  Cmd.ProtocolId = SCMI_PROTOCOL_ID_BASE;
  Cmd.MessageId  = MessageId;

  PayloadLength = 0;

  Status = ScmiCommandExecute (
             &Cmd,
             &PayloadLength,
             &ReturnValues
             );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  AsciiStrCpyS (
    (CHAR8*)VendorIdentifier,
    SCMI_MAX_STR_LEN,
    (CONST CHAR8*)ReturnValues
    );

  return EFI_SUCCESS;
}

/** Return vendor name.

  @param[in] This           A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] VendorIdentifier Null terminated ASCII string of up to
                               16 bytes with a vendor name.

  @retval EFI_SUCCESS       VendorIdentifier is returned.
  @retval EFI_DEVICE_ERROR  SCP returns a SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
STATIC
EFI_STATUS
BaseDiscoverVendor (
  IN  SCMI_BASE_PROTOCOL  *This,
  OUT UINT8               VendorIdentifier[SCMI_MAX_STR_LEN]
  )
{
  return BaseDiscoverVendorDetails (
           SCMI_MESSAGE_ID_BASE_DISCOVER_VENDOR,
           VendorIdentifier
           );
}

/** Return sub vendor name.

  @param[in]  This           A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] VendorIdentifier Null terminated ASCII string of up to
                               16 bytes with a sub vendor name.

  @retval EFI_SUCCESS       VendorIdentifier is returned.
  @retval EFI_DEVICE_ERROR  SCP returns a SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
EFI_STATUS
BaseDiscoverSubVendor (
  IN  SCMI_BASE_PROTOCOL  *This,
  OUT UINT8               VendorIdentifier[SCMI_MAX_STR_LEN]
  )
{
  return BaseDiscoverVendorDetails (
           SCMI_MESSAGE_ID_BASE_DISCOVER_SUB_VENDOR,
           VendorIdentifier
           );
}

/** Return implementation version.

  @param[in] This           A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] ImplementationVersion Vendor specific implementation version.

  @retval EFI_SUCCESS       Implementation version is returned.
  @retval EFI_DEVICE_ERROR  SCP returns a SCMI error.
  @retval !(EFI_SUCCESS)    Other errors.
**/
STATIC
EFI_STATUS
BaseDiscoverImplVersion (
  IN  SCMI_BASE_PROTOCOL  *This,
  OUT UINT32              *ImplementationVersion
  )
{
  EFI_STATUS    Status;
  UINT32        *ReturnValues;
  SCMI_COMMAND  Cmd;
  UINT32        PayloadLength;

  Cmd.ProtocolId = SCMI_PROTOCOL_ID_BASE;
  Cmd.MessageId  = SCMI_MESSAGE_ID_BASE_DISCOVER_IMPLEMENTATION_VERSION;

  PayloadLength = 0;

  Status = ScmiCommandExecute (
             &Cmd,
             &PayloadLength,
             &ReturnValues
             );
  if (EFI_ERROR (Status)) {
    return Status;
  }

  *ImplementationVersion = ReturnValues[0];

  return EFI_SUCCESS;
}

/** Return list of protocols.

  @param[in]  This           A Pointer to SCMI_BASE_PROTOCOL Instance.

  @param[out] ProtocolListSize  Size of the ProtocolList.

  @param[out] ProtocolList   Protocol list.

  @retval EFI_SUCCESS          List of protocols is returned.
  @retval EFI_BUFFER_TOO_SMALL ProtocolListSize is too small for the result.
                                It has been updated to the size needed.
  @retval EFI_DEVICE_ERROR     SCP returns a SCMI error.
  @retval !(EFI_SUCCESS)       Other errors.
**/
STATIC
EFI_STATUS
BaseDiscoverListProtocols (
  IN     SCMI_BASE_PROTOCOL  *This,
  IN OUT UINT32              *ProtocolListSize,
  OUT    UINT8               *ProtocolList
  )
{
  EFI_STATUS          Status;
  UINT32              TotalProtocols;
  UINT32              *MessageParams;
  BASE_DISCOVER_LIST  *DiscoverList;
  UINT32              Skip;
  UINT32              Index;
  SCMI_COMMAND        Cmd;
  UINT32              PayloadLength;
  UINT32              RequiredSize;

  Status = BaseGetTotalProtocols (This, &TotalProtocols);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  Status = ScmiCommandGetPayload (&MessageParams);
  if (EFI_ERROR (Status)) {
    return Status;
  }

  RequiredSize = sizeof (UINT8) * TotalProtocols;
  if (*ProtocolListSize < RequiredSize) {
    *ProtocolListSize = RequiredSize;
    return EFI_BUFFER_TOO_SMALL;
  }

  Cmd.ProtocolId = SCMI_PROTOCOL_ID_BASE;
  Cmd.MessageId  = SCMI_MESSAGE_ID_BASE_DISCOVER_LIST_PROTOCOLS;

  Skip = 0;

  while (Skip < TotalProtocols) {

    *MessageParams = Skip;

    // Note PayloadLength is a IN/OUT parameter.
    PayloadLength = sizeof (Skip);

    Status = ScmiCommandExecute (
               &Cmd,
               &PayloadLength,
               (UINT32**)&DiscoverList
               );
    if (EFI_ERROR (Status)) {
      return Status;
    }

    for (Index = 0; Index < DiscoverList->NumProtocols; Index++) {
      ProtocolList[Skip++] = DiscoverList->Protocols[Index];
    }
  }

  *ProtocolListSize = RequiredSize;

  return EFI_SUCCESS;
}

// Instance of the SCMI Base protocol.
STATIC CONST SCMI_BASE_PROTOCOL BaseProtocol = {
  BaseGetVersion,
  BaseGetTotalProtocols,
  BaseDiscoverVendor,
  BaseDiscoverSubVendor,
  BaseDiscoverImplVersion,
  BaseDiscoverListProtocols
};

/** Initialize Base protocol and install protocol on a given handle.

   @param[in] Handle              Handle to install Base protocol.

   @retval EFI_SUCCESS            Base protocol interface installed
                                  successfully.
**/
EFI_STATUS
ScmiBaseProtocolInit (
  IN OUT EFI_HANDLE* Handle
  )
{
  return gBS->InstallMultipleProtocolInterfaces (
                Handle,
                &gArmScmiBaseProtocolGuid,
                &BaseProtocol,
                NULL
                );
}
